Always used to leave that one off if a DCA/DOT/CASA inspection was due. They used to fuss around and make a big thing of it saying it was essential for aircraft operation. One chap gave me a big lecture about how I should take more care. The aircraft was facing 230 the compass was indicating 330, he noticed the compass deviation card wasn't here but didn't look at the compass ? I admit I neglected to point it out to him. He snagged me and sent out a list of things he said needed attention. One of which he claimed was a cracked exhaust, I knew it wasn't. After taking it off inspecting and using dye penetrant there were no cracks, another $300 spent.